1. Technical Field
The present disclosure relates to an all-solid-state lithium-ion secondary battery and method for manufacturing that.
2. Description of the Related Art
In recent years, all-solid-state lithium-ion secondary batteries (hereinafter “all-solid-state batteries”), which are composed solely of solid components including an electrolyte, have been receiving attention. A disadvantage of all-solid-state batteries as compared with organic liquid electrolyte-based batteries is that they do not charge and discharge quickly due to high resistance at the interface between a cathode active material and a solid electrolyte.
As a solution to this, Masakazu Haruta et al. discloses a method for reducing the interface resistance of all-solid-state batteries in which the cathode active material and the solid electrolyte are LiCoO2 and LiPON (a nitride of lithium phosphate), respectively (Nano Letters 15, 1498 (2015)). With this method, the reduction of the interface resistance is achieved through the formation of a high-quality interface. This method includes forming a LiCoO2 layer and a LiPON layer sequentially by PLD (pulsed laser deposition) and sputtering, respectively, in an ultrahigh vacuum. During the formation of the LiPON layer by sputtering, the target and the substrate are positioned off-axis.
Japanese Patent No. 4982866 discloses a configuration in which LiNbO3 is disposed between layers of LiCoO2 as a cathode active material and Li2S—P2S5 as a solid electrolyte.